Getting user access token via admin access token

Getting advice
1

I have a Keycloak server for SSO. In this server, there may be many users. I need a way to obtain an access token for a specific user (for example, John in the realm ‘test_realm’) using an admin account from the master realm. I only have the user’s user ID or username and do not have the user’s password. How can I do that?

Version: 25.0.4

2

Does impersonation fit your use-case?

3

I trayed with impersonation and it will give me redirect url. I want to get access token.